Nidec Control Techniques HVAC Drive H300 HMI Bypass, Installation And Commissioning Manual

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HMI Bypass Controller Installation and Commissioning Guide 27
3.2.4 Skip Frequencies
The skip reference functions are available to prevent continuous operation
within a specified speed range (i.e., where mechanical resonance may occur).
The HMI Bypass allows up to three (3) speed/frequencies to be skipped.
Skip Reference : Sets the center point of the speed/frequency reference the
VFD should skip.
Band Width : Defines the range which speed/frequency references are
rejected in either direction. The actual reference band is, therefore, twice that
defined in the Band Width, with Skip Reference as the center of the band.
3.2.5 Motor Ramp/Limits
The Motor Ramps/Limits screen allows configuration of speed/frequency limits
as well as acceleration and deceleration values the VFD will use during motor
start and stop.
Max Switching Freq: Defines the maximum switching frequency used by the drive.
If drive will operate at this frequency unless the inverter becomes too hot. Under
these conditions the drive will reduce switching frequency to avoid tripping.
Minimum Frequency : Defines the minimum value for the reference.
Maximum Frequency : Defines the maximum value for the reference.
Generally set to 60 Hz or less.
Accel Time : Defines the rate of acceleration. This is the time to accelerate
from minimum frequency to maximum frequency.
Decel Time : Defines the rate of deceleration. This is the time to decelerate
from maximum frequency to minimum frequency.